ES2903094T3 - Device to ensure a safety zone around at least one machine that works automatically - Google Patents

Abstract

Device to ensure a safety zone around at least one machine (3) that works automatically, comprising - a luminous marking (4; 5) in a visible or invisible way, arranged on or in at least one surface (2) that delimits the security zone, whereby at least a part of the security zone and/or at least a part of a delimitation of the security zone is marked, - a sensory monitoring device configured to detect a violation of the security zone security, where the supervision device comprises a sensor system sensitive to touch, with spatial resolution and/or a capture device (12) for image supervision of the luminous marking of the security zone, - a control device (1) configured to control the machine (3) and/or to determine the safety zone from an operating state of the machine (3) and/or to control a shape, a structure and/or a place of the luminous marking (4; 5) and further configured to change the operating status of the machine (3) and/or to change the operating mode of at least one light source (6, 7) and/or to trigger an alarm based on a violation detection of the security zone by means of the supervision device, where a plurality of light sources (6, 7) excitable with spatial resolution is arranged on or on the surface (2) that delimits the security zone, each of the light sources light (6, 7) comprises an inactive and at least one active operating mode, where the operating mode of the light sources can be controlled by the control device, and the luminous marking (4; 5) is configured as at least one of the light sources (6, 7) in an active operating mode; characterized in that the operating mode of each of the light sources (6, 7) can be individually controlled by the control device (1).

Description

DESCRIPTION

Device for ensuring a safety zone around at least one machine that works automatically The invention relates to a device for ensuring a safety zone around a machine that works automatically, in particular in a work area used jointly by people and machines , according to the preamble of main claim 2.

In work spaces that are used jointly by people and machines, such as autonomously operating machines and/or robots, it must be excluded at all times that people are injured by the machines. In this case, injuries can occur, for example, due to collisions of people and machines or also due to the projection of sparks that originate from the work of the machine.

In order to prevent such injuries, a safety zone is defined for each machine, where the safety zone can be static or dynamic depending on the current work or a movement of the machine. The security zone is then monitored by means of various security techniques, for example laser scanners, light barriers, camera-based sensor systems, projection-based sensor systems or tactile floor coverings. These safety techniques detect the distance of a person from the source of danger and, in the event of a detected violation of the safety zone, a safety-relevant function of the machine is triggered, for example, the machine is put into a state of emergency stop, the machine work is slowed down or a dangerous part of the machine is stopped or spatially removed. However, in most cases this safety distance is not perceptible or only insufficiently perceptible to people. Therefore, in practice, it often happens that a person accidentally enters the safety zone of a machine and thus unintentionally stops the installation.

From EP 2558886 B1 a device for monitoring a three-dimensional danger zone is presented. In this case, the supervision is carried out by projected luminous markings that are supervised by a camera system. In this way, a device is described to secure a security zone in which a machine that works automatically is located, where this security device comprises a projected marking, luminous in a visible or invisible way. This marking is arranged on a surface that delimits the security zone and marks at least a part of the security zone and/or at least a part of a delimitation of the security zone. Furthermore, from EP 2558886 B1 a control device is known, which can be used to control the machine, to determine the safety zone of an operating state of the machine and/or to control a shape, structure and/or a place of light marking.

Furthermore, US 2006/0082465 A1 discloses a monitoring system for a machine, which consists of a switch mat that is electrically connected to the machine. The switch mat is placed on the floor next to the machine and comprises a pressure triggered switch mechanism so that power to the machine is switched off when pressure is exerted on the mat. In addition, the switch mat contains a status indicator display, which lights up according to the status of the machine.

The present invention has the object of creating a device for securing a security zone, which is simple in its structure and by means of which a display of the security zone is guaranteed.

This object is achieved by the features of the main claim. Advantageous improvements are described by the dependent claims.

In the device for securing a security zone or for marking the security zone according to the preamble of the main claim of the present application, a plurality of spatially resolved excitable light sources are arranged on the surface, such as a floor, a wall, a table and/or a surface of the machine that delimits the safety zone. Each of these light sources comprises at least one inactive operating state, for example "off" or "standby", as well as at least one active operating state, for example "on" or "blinking", where the operating state of the light sources can be controlled by the control device In this connection, the marking is configured as at least one of the light sources in an active operating mode.

One can speak, for example, of a marking of the security zone, as long as it is only marked, one can speak of an assurance, for example, as long as the marking highlights the security zone and, therefore, the secure. Furthermore, one can then also speak of a security if the security zone also comprises, in addition to the marking, a device for monitoring the security zone.

Therefore, the light marking is self-luminous and directly controllable. Shading of the marking by the machine to be secured can be avoided.

In the event of an autonomous or otherwise caused movement of the machine, which is situated in the safety zone, the safety zone and/or the light marking can be changed dynamically by the control device and in correspondence with the movement of the machine in response to the movement and/or the associated change in the state of operation of the machine.

Thus, a dynamic safety zone is created which is adapted to the current danger situation emanating from the machine at any time. A movement of the machine in the direction mentioned above can change the location of the machine, but it does not have to. Rather, it is also possible that the machine stays in one place and only a part of the machine moves, for example a gripper arm or a saw blade. By means of such a movement, a change of the safety zone can be induced in order to secure, for example, the radius of action of a machine part or a zone in which a projection of sparks or chips is to be expected.

It is also possible that the control device is further configured to change the safety zone of the machine depending on a change in the operating state of the machine. For example, a disconnected machine does not require a security zone or only a very small security zone. When the machine is put into operation, the safety zone is automatically extended by the control device based on the operating data of the machine. Already during standby operation, a larger safety zone can be induced so that no one is in the immediate vicinity of the machine during machine start-up.

The various desired safety zones for the possible operating states of a machine can be individually defined and possibly changed within the legally prescribed standards by a correspondingly trained user.

In the event of a change of the security zone, the light marking preferably automatically adapts to the new security zone. In this connection, the light marking and/or the mode of operation of at least one of the light sources can be changed. For example, by means of the control device, light sources that are no longer needed for marking the new security zone can be switched off and other light sources that are used can be put into an active operating mode by means of the control device. Until now, they were in an idle mode of operation.

In this case, it is possible that the old safety zone remains visible at first, which can be advantageous precisely when switching off a machine, if sources of danger, such as waste products produced during machine operation, they can still be located within the old security zone.

According to the invention, the mode of operation of each of the light sources can be individually controlled by the control unit. Thanks to the individual controllability a high flexibility in the design of the illuminated marking is achieved. Alternatively, it is also possible that the light sources can be controlled in blocks or rows. It is also possible, with the individual controllability of the light sources, to define groups of individual light sources in order to simplify the control of the light sources that are mostly driven together.

Furthermore, the light sources can be modulated in their color, brightness and/or frequency. Thus, it is possible to mark different security zones differently, or to convey additional information to a person in a color-coded and/or visualized manner by marking. For example, different colors can be used for different levels of danger.

Furthermore, it is possible, in addition to the marking of the safety zone, to transmit additional information via the light sources to a person, for example information on the anticipated operating time of a machine, on a required maintenance of the machine or on the type of danger emanating from the machine. This additional information can be transmitted to a user, for example, in the form of pictograms or illuminated writing.

In addition, it is also possible to mark a security zone invisible to the human eye by means of infrared light, for example, if there are no people near the security zone, or if a visible light marking would be disturbing for sequences of I work in an area.

The marking of a security zone can be flat or made by means of lines, contours or patterns, where depending on the design of the space and the security zone, a complete circular course should not be necessary to mark a delimitation of the security zone .

Furthermore, the control device can further be configured to divide the safety zone, for example depending on a movement and/or a change in the operating state of the machine, into at least a first and a second safety zone. , whereby at least part of the first security zone and/or at least part of a delimitation of the first security zone, as well as at least part of the second security zone and/or at least a part of a delimitation of the second security zone.

On some machines it is advantageous if the safety zone around the machine is subdivided into several safety levels, so that in the event of a violation of a zone of a lower safety level being detected by the control device, a different reaction than in the case of a violation of a zone of a higher security echelon.

In this case, it is possible that at least two different security zones disjoined, interspersed and/or overlapped with each other and/or security steps of a security zone are marked by different colors, brightness and/or frequencies of the light sources .

By marking different safety zones and/or safety steps with different colors, a user can better estimate the danger potential of individual machines and/or workspace zones.

The light sources can preferably be configured in the form of points, for example in the form of single or multi-colored LEDs. The use of RGB LEDs, which can reproduce a particularly wide color spectrum, can be advantageous in this case. Using such small light spots, the markings can be designed particularly flexibly and precisely.

In addition, the light sources can be arranged regularly and/or in the form of a matrix on or on the surface that delimits the security zone, preferably with a narrow mesh, for example at a distance of at most 10 cm, preferably at most 5cm The distance can preferably be selected such that it is to be expected with a high probability that, in the event of a violation of the security zone, at least one of the light sources is at least temporarily obscured - for example by a person or an external object to the machine. Therefore, it is possible to provide a work zone on a large surface with light sources, which can then be activated by the control device as a function of one or more safety zones to mark the safety zone(s).

In order to achieve the simplest and flattest possible equipping of a work area with light sources, the light sources can be arranged on light mats that can be easily laid out and connected. For example, the light mats can be supplied in the form of tiles or as rolled strips and can then be laid, applied or possibly fixed on a surface, for example a floor, a wall, a work table or any other surface to be will of the work area.

Furthermore, the security device comprises a sensory monitoring device, by means of which a violation of the security zone can be detected. Depending on the detection of a security zone violation by the monitoring device, e.g. when a person enters the security zone, a security-relevant function can be triggered by the control device, e.g. the operating state of the machine that is located in the security zone can be changed, the operating mode of at least one of the light sources can be changed or an alarm can be triggered. Preferably, upon detecting a violation of the safety zone, the machine can be switched off or switched to another safe operating state, possibly in combination with a change in the shape, structure and/or location of the luminous marking. In addition, for example, an acoustic or visual alarm can be triggered. In this case, the visual alarm can also refer to the light marking, for example by flashing the light marking. By means of a visual alarm a user's attention can be directed to the marking and the security zone in a locally limited manner. If an acoustic alarm is used, the alarm can still be noticed at a greater distance.

In this case, the monitoring device may comprise a spatially resolved, touch-sensitive sensor system, for example, as described in EP2147502 B1. Said sensor system is made up of a plurality of sensor cells that are arranged on or on the surface that delimits the security zone. In this case, the sensor cells can be arranged, for example, as tactile sensor mats, by means of which the force and location of a contact can be detected.

A violation of the security zone can be detected with the help of the touch-sensitive sensor system if the sensor system has registered a touch above a defined threshold value. In this case, the threshold value can be selected so that the entry of a person into the security zone can be detected. On the other hand, by means of the supervision device small contacts can be tolerated to avoid an unjustified shutdown of the machine.

It may be advantageous if at least one of the light sources is locally associated with each of the plurality of sensor cells. Therefore, it is possible for the sensor cells to be larger than or equal to the size of the individual light sources. By means of the control device, the individual sensor cells and the associated light sources can be functionally coupled, so that an automatic marking of an area in which a contact has been detected is possible.

Separate sensor mats and light mats can be applied one on top of the other on the delimiting surface the security zone. In this case, it is advantageous if the mats are provided such that the upper mat does not impair the functionality of the lower mat. For this, the mats can be made, for example, very thin and/or transparent.

Furthermore, it is possible to configure the light sources and the touch-sensitive sensor cells in combined light-sensing mats, which can be laid on the surface delimiting the security zone. By means of the combined light-sensing mats it is possible to avoid the problems described above during the laying of two layers. Furthermore, in the case of combined light-sensing mats, the functional linkage of the sensor cells and light sources can be provided directly.

Furthermore, it is also possible for the monitoring device to comprise a detection device, for example at least one camera for image monitoring of the security zone or a laser scanner. The movements of people and machines in the work zone can be recorded by a sensor device, and an approach of a person to a machine or an entrance and/or other violation of the safety zone around a machine by the user can be detected. of the person.

By using a pickup device via the monitoring device, a violation of the safety zone can be detected by the monitoring device, for example, if at least a predetermined number of the light sources marking the safety zone are not detected by the pickup device. In this case, for example, the detection can be carried out analogously to the method described in EP 2558886 B1 for comparing a real image with a reference image.

To increase security, it is also possible to simultaneously secure a security zone by means of a touch-sensitive sensor system and a pickup device. In this case, the risk of a failure of the monitoring device is minimized and thus a higher safety category is achieved.

Although so far a device for securing a safety zone has been discussed most of the time, the application also encompasses a use of a device for securing the safety zone according to this description or one of the claims during the operation of a machine . To do this, the marking of the safety zone is displayed and adapted depending on the location of the machine (such as a robot equipped, for example, with a tool). The embodiments of use can be inferred from this application.

In addition, the application also includes a procedure to secure a security zone. In this regard, a device for securing a security zone can be applied according to the request.

First of all, a safety zone of a machine is determined, which can be defined, for example, by the radius of action of a machine part (such as a robot arm) and possibly an additional safety distance. In this connection, the safety zone can be measured or recorded externally, ie by means of a monitoring device, or it can be transmitted by the machine to a control device of a device for securing the safety zone.

After defining the security zone, the control device controls the light sources that are arranged on a surface surrounding the security zone. Due to the activation by the control device, the light sources can mark, for example, a boundary of the security zone, the entire security zone or the security zone surrounding the security zone.

In various embodiments, the safety zone is again defined, for example, depending on the machine configuration (for example, in the case of a robot arm tool change) or depending on the location of machine and the control device registers and marks the new or updated security zone. Other embodiments can be deduced from the application.

The embodiments described in the context of a use or a method can also be claimed in the device according to any of the claims.

Other advantageous embodiments will be described below with reference to the figures. In this case, Fig. 1 shows a plan view of a safety zone around a machine with light markings,

Fig. 2 a change in the safety zone in the event of a machine movement,

Fig. 3 a plan view of a surface with LEDs in the form of points,

Fig. 4 a cross section of a multilayer surface covering of LEDs and sensor cells,

Fig. 5 a cross section of a combined light-sensing mat,

Fig. 6 an LED floor with additional camera monitoring and

Fig. 7 the LED floor with camera monitoring from fig. 6, where a subset of the LEDs is covered. In fig. 1 shows a floor 2 of a work area that is used jointly by humans and robots. A robot 3 is located in this work zone. For example, a two-step safety zone of the robot 3 is determined by means of a control device 1 based on the operating status of the robot 3. The control device controls the LEDs that they are arranged on the floor in such a way that two illuminated marking circles 4, 5 mark the robot's safety zone. In this case, the inner marking 4 lights up red and therefore shows a high safety step, while the outer marking 5 lights up yellow and therefore shows a lower safety step. Furthermore, further LEDs are arranged on the floor 2, which are currently not used to mark the security zone and are not shown in the figure.

By means of the markings 4, 5, the safety zone around the robot 3 can be easily recognized by a person, so that the risk of inadvertent entry into the safety zone is reduced.

If the robot 3 now moves to a new position 3' in the work area, then a new safety area is determined by the control device 1 and marked by an LED light marking 4'. By means of the control device, the old LED light marking 4 is switched off in response to the movement of the robot. Thus, the marking 4, 4' can dynamically identify the current safety zone of the robot 3.

the fig. 3 shows a more detailed plan view of a surface 2 that is equipped with LEDs 6, 7 arranged in a matrix form. The outline of the safety zone of a machine not shown is marked by illuminated LEDs 7, while the remaining LEDs 6 are placed in an inactive operating mode.

In addition to the visible marking 7 of the security zone, a laser scanner 8 is used in this exemplary embodiment to monitor the security zone. The security zone, the security zone marking 7 and the laser scanner 8 are coupled via the control device. Therefore, the laser scanner can monitor the security zone (for example, by rotary scanning) for objects located in it, such as objects or people. If an object is detected by the laser scanner 8, then the distance of the laser scanner to the object can be determined by the control device and it can be deduced from this whether there is a violation of the safety zone.

If a violation is detected, then the control device can induce the shutdown of the machine around which the security zone is situated. In addition, in case of violation of the security zone, a warning or alarm signal can be generated in the form of flashing LEDs.

Instead of the laser scanner shown in figure 3, additional monitoring devices can also be used to recognize a violation of the marked safety zone. According to an embodiment shown in FIGS. 4 and 5, the floor can comprise additional tactile sensors in the work area, by means of which it is possible to recognize where people are in the work area.

A possible floor structure according to this example of embodiment is shown in fig. 4. In this case, two additional layers 9 and 10 are applied to the floor 17. The lower of the two layers consists of a tactile sensor mat 9, which is subdivided into several sensor cells 18. By means of the sensor cells it is possible to detect an entrance of a person on the ground with spatial resolution. Information about the location and type of entry is then transmitted to the control device.

The upper of the two layers shown in Figure 4 comprises an LED mat, by means of which multicolored RGB LEDs are applied, arranged regularly on the ground. These LEDs are individually controlled by the control device, whereby it is possible to characterize a safety zone flexibly and precisely by means of LED light marking. By using LED mats, on which the LEDs are closely arranged, it is also possible to display other warnings by means of luminous RGB LEDs that can reproduce a wide spectrum of colors.

In this case, a number of LEDs 6 are locally assigned to each sensor cell 18 and are virtually linked by the control device, so that it is possible to selectively excite the LEDs assigned to the sensor cell 18 when a contact with the sensor cell has been detected. sensor cell 18.

According to another example of embodiment, the sensor cells and the LEDs, as shown in fig. 5, are applied to the floor 17 as a combined light sensor mat 11. In this case, the light sensor mat 11 comprises several sensor cells 18, each of which is assigned a fixed number of LEDs 6. By means of a mat Combined light sensor provides a direct, hardwired assignment between the sensor cells and the LEDs.

According to another example of embodiment not shown in the figures, the LED mats, the sensor mats and the mats Combined light sensors can also be laid on other surfaces, for example on walls, on tables or on surfaces of a machine.

Figs. 6 and 7 show another embodiment of the LED floor with additional camera monitoring. In this case, the LEDs 6, 7, which mark a safety zone of a floor 2 of a work area, are recorded by a camera 12. In this case, the monitoring device receives, on the one hand, information from the device control over the setpoint image, which is made up of the currently active LEDs and their coordinates in the work area. Furthermore, thanks to the camera 12, the monitoring device obtains a real image 13 of a monitoring area 14 from the camera 12.

In this case, the light emitted by the LEDs can be located in a visible or non-visible (infrared) spectrum. The camera is adapted to the respective wavelength to avoid external influences. Depending on the size and layout of the work area, camera systems with multiple cameras can also be used.

The actual recorded image is compared with the setpoint image, where it is sufficient to compare only the pixels of the relevant coordinates of the light marking by addition or subtraction. If the real image 13 corresponds to the setpoint image, as shown in fig. 6, then through the monitoring device does not detect any violation of the security zone.

However, if, as shown in fig. 7, some LEDs 7 of the light marking are hidden, then this may indicate the penetration of a person in the safety zone of the machine. In this case, the actual image 13' no longer corresponds to the setpoint image. This discrepancy between the two images is detected by the monitoring device and transmitted to the control device. The control device then stops the operation or dangerous movement of the machine located in the safety zone and triggers an alarm. According to another embodiment, it is also possible to combine the tactile floor, as shown in figs. 4 and 5, with camera supervision, as shown in figs. 6 and 7. In this way, together with the marking of the security zone, a double and redundant supervision is implemented with various sensor principles of the security zone, so that in the event of failure or defective behavior of one of the supervision systems a high degree of human safety can be guaranteed in a common working area for people and robots.

Claims (15)

1. Device to ensure a safety zone around at least one machine (3) that works automatically, comprising - a visible or invisible luminous marking (4; 5), arranged on or on at least one surface (2) that delimits the security zone, through which at least part of the security zone is marked and/or at least part of a delimitation of the security zone, - a sensory monitoring device configured to detect a violation of the security zone, where the monitoring device comprises a sensor system sensitive to touch, with spatial resolution and/or a sensor device (12) for image monitoring of the light marking of the safety zone, - a control device (1) configured to control the machine (3) and/or to determine the safety zone from an operating state of the machine (3) and/or to control a form, a structure and/or a place of the luminous marking (4; 5) and further configured to change the operating state of the machine (3) and/or to change the operating mode of at least one light source (6 , 7) and/or to trigger an alarm based on a detection of a security zone violation by the monitoring device, where a plurality of light sources (6, 7) excitable with spatial resolution is arranged on or in the surface (2) that delimits the security zone, each of the light sources (6, 7) comprises an inactive mode of operation and at least one active, where the operating mode of the light sources can be controlled by the control device, and the light marking (4; 5) is configured as at least one of the light sources (6, 7) in an active operating mode; characterized in that the operating mode of each of the light sources (6, 7) can be individually controlled by the control device (1). Device for securing according to claim 1, characterized in that the monitoring device comprises the touch-sensitive sensor system, which is a spatially resolved touch-sensitive sensor system comprising a plurality of sensor cells (18), which are arranged on or on the surface (2) that delimits the security zone. Device for securing according to claim 2, characterized in that the monitoring device is configured to detect a violation of the security zone when a contact above a predetermined threshold value within the security zone is registered by the sensor system. Device for securing according to claim 2 or 3, characterized in that each of the plurality of sensor cells (18) is locally associated with at least one of the light sources (6, 7) and, optionally, in that the plurality of light sources (6, 7) and sensor cells (18) are configured as combined light sensor mats (11). Device for securing according to any of the preceding claims, characterized in that the monitoring device comprises the sensor device (12) for image monitoring of the luminous marking of the security zone. Device for securing according to claim 5, characterized in that the monitoring device is configured to detect a violation of the security zone if at least a predetermined number of the light sources (6, 7) marking the security zone do not are recorded by the capture device (12). Device for securing according to one of the preceding claims, characterized in that the monitoring device is configured as a laser scanner (8). Device for securing according to any one of the preceding claims, characterized in that the light sources (6, 7) are in the form of points and/or in that the light sources (6, 7) are arranged on or in the surface ( 2) regularly and/or in the form of a matrix and/or narrow mesh with a maximum distance of 10 cm. 9. Device to secure according to any of the preceding claims, characterized in that the control device (1) is configured to change the security zone dynamically and in correspondence with the movement of the machine (3) during a movement of the machine (3). Device for securing according to any of the preceding claims, characterized in that the control device (1) is further configured to - change the security zone depending on a change in the operating status of the machine (3) and/or - in case of change of the security zone, change the marking (4; 5) and/or the mode of operation of at least one of the light sources (6, 7). Device to secure according to any of the preceding claims, characterized in that the light sources (6, 7) can be modulated in their colour, brightness and/or frequency by the control unit (1), and/or in that at least a subset of the plurality of light sources (6, 7) are arranged on or in light mats (10). 12. Device to secure according to any of the preceding claims, characterized in that the control device (1) is further configured to divide the security zone into at least a first and a second security zone, where by means of the luminous marking (4; 5) at least a part of the first security zone and/or at least a part of a delimitation of the first security zone is marked, as well as at least a part of the second security zone and/or at least a part of a delimitation of the second security zone. 13. Device to ensure according to any of the preceding claims, characterized in that at least two different or disjoint security zones, interspersed and/or superimposed on each other and/or security steps of a security zone are marked by different colors, brightness and /or frequencies of the light sources (6, 7). 14. Use of a device according to any of claims 1 to 13 to secure a safety zone of a machine. 15. Procedure for securing a security zone of a machine (3), where the procedure comprises the following steps: - determination of a safety zone of a machine (3); - excitation, by means of a control device (1), of the excitable light sources (6, 7) with spatial resolution, which are arranged on or on at least one surface (2) that delimits the security zone, in such a way marking the safety zone of the machine (3), where each of the light sources (6, 7) comprises an inactive and at least one active operating mode that can be controlled by the control device (1) , - detection of a violation of the security zone by means of a sensory monitoring device, where the monitoring device comprises a sensor system sensitive to touch, with spatial resolution and/or a capture device (12) for image monitoring of the marking safety zone light, - changing an operating state of the machine (3) and/or changing the operating mode of at least one light source (6, 7) and/or triggering an alarm when a violation of the safety zone has been detected security; characterized in that the operating mode of each of the light sources (6, 7) can be individually controlled by the control device (1).